3-(2,6-Dichloro-3,5-dimethoxy-phenyl)-1-{6-[4-(4-ethyl-piperazin-1-yl)-phenylamino]-pyrimidin-4-yl}-1-methyl-urea (described in U.S. Ser. No. 11/570,983, filed Jun. 23, 2005, and incorporated by reference in its entirety herein) has the structure of Formula I:

The compound of Formula I (referred as the Compound hereafter) is a protein kinase inhibitor and is useful in the treatment of proliferative diseases mediated by protein kinases. In particular, the Compound inhibits FGFR1, FGFR2, FGFR3, FGFR4.
Several crystalline and amorphous forms of the Compound and methods to preparing said forms were described in WO 2011/071821 and are incorporated by reference in its entirety herein.